Shutter units are available within a circuit breaker compartment for preventing inadvertent contact with the compartment power stabs. One such unit is described within U.S. patent application (41DA-6145) which is incorporated herein for purposes of reference. A shutter mechanism is integrally coupled with the circuit breaker assembly for opening a pair of shutters to provide access between circuit breaker receptacles and the compartment power stabs when the circuit breaker is inserted within the compartment. Withdrawal of the circuit breaker unit from the compartment causes the shutter mechanism to close and thereby prevent direct access with the voltage available at the power stabs. U.S. Pat. Nos. 3,614,350, 4,183,073 and 4,285,026 also disclose various configurations of a shutter arrangement within a circuit breaker compartment. In view of the increasing safety requirements for circuit breaker compartments already in operation that do not contain a shutter safety mechanism, there is a need for a field installable shutter safety mechanism that fits circuit breaker compartment designs of various manufacture.
The purpose of this invention is to provide a self-contained shield arrangement for assembling within a circuit breaker compartment in the field, without substantial modification to either the circuit breaker assembly or the circuit breaker compartment.